[Fleet] Added all privilege to kibana_system to logs-fleet_server.* index pattern (#106815) (#106863)

* Update KibanaOwnedReservedRoleDescriptors.java

* replaced all with read, delete_index

Author: juliaElastic

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/security/authz/store/KibanaOwnedReservedRoleDescriptors.java

@@ -198,7 +198,7 @@ static RoleDescriptor kibanaSystem(String name) {
                 // Fleet publishes Agent metrics in kibana task runner
                 RoleDescriptor.IndicesPrivileges.builder().indices("metrics-fleet_server*").privileges("all").build(),
                 // Fleet reads output health from this index pattern
-                RoleDescriptor.IndicesPrivileges.builder().indices("logs-fleet_server*").privileges("read").build(),
+                RoleDescriptor.IndicesPrivileges.builder().indices("logs-fleet_server*").privileges("read", "delete_index").build(),
                 // Legacy "Alerts as data" used in Security Solution.
                 // Kibana user creates these indices; reads / writes to them.
                 RoleDescriptor.IndicesPrivileges.builder().indices(ReservedRolesStore.ALERTS_LEGACY_INDEX).privileges("all").build(),